Wirelessly Powered Coil-Type Robot with 1D Self-Actuation Capability

This paper proposes a system that can actuate itself with wirelessly received power. The system consists of two coils with different purposes; the power-receiving coil wirelessly receives power from the external sinusoidal magnetic field, and the actuation coil controls the current for 1D self-actuation. The actuation current has a square waveform and is controlled to be in phase with the external magnetic field. The average force applied to the robot is proportional to the magnitude of the actuation current. In order to improve the control performance, the actuation coil is designed with the consideration of the flux distribution. By the design, the external magnetic field does not induce a voltage on the actuation coil. The proposed design and control were verified with the implemented cylindrical prototype robot which had 18 mm radius and 34 mm height.